Deep-level transient spectroscopy was used to investigate the Si-related DX center in heavily doped ion-implanted material. The experimental results revealed the existence of 2 intrinsic levels that were related to the DX center. These were a low-temperature peak with an activation energy of 0.270eV and high-temperature peak with an activation energy of 0.315eV. These 2 levels were suggested to arise from a splitting of the DX ground state via a Coulombic contribution to inter-valley scattering in the L-band. A difference between the emission activation energies of the DX center in GaAs and AlGaAs was explained in terms of a strongly perturbing effect of the Al atom upon the energy level of the defect orbital.

S.Ghosh, V.Kumar: Solid State Communications, 1996, 98[2], 195-9